Different plants have seed contents that make them desirable for feed compositions. Examples are soybean, canola, rapeseed and sunflower. After crushing the seeds and recovering the oil, the resulting meal has a protein content making the meal useful as a feed ingredient for ruminants, monogastrics, poultry, and aquaculture. Nevertheless, there remains a desire for improved plant seeds that can provide additional sources of nutrition to animals.
Field Pennycress Thlaspi arvense L. (common names: fanweed, stinkweed, field pennycress), hereafter referred to as Pennycress or pennycress, is a winter cover crop that helps to protect soil from erosion, prevent the loss of farm-field nitrogen into water systems, and retain nutrients and residues to improve soil productivity. While it is well established that cover crops provide agronomic and ecological benefits to agriculture and environment, only 5% of farmers today are using them. One reason is economics—it requires on average ˜$30-40/acre to grow a cover crop on the land that is otherwise idle between two seasons of cash crops such as corn and soy. In the last 5 years, it has been recognized that pennycress could be used as a novel cover crop, because in addition to providing cover crop benefits, it is an oilseed with its oil being useful as a biofuel. Extensive testing indicates that it can be interseeded over standing corn in early fall and harvested in spring prior to soybean planting (in appropriate climates). As such, its growth and development requires minimal incremental inputs (e.g., no/minimum tillage, no/low nitrogen, insecticides or herbicides). Pennycress also does not directly compete with existing crops when intercropped for energy production, and the recovered oil and meal can provide an additional source of income for farmers.
Pennycress is a winter annual belonging to the Brassicaceae (mustard) family. It's related to cultivated crops, rapeseed and canola, which are also members of the Brassicaceae family. Pennycress seeds are smaller than canola, but they are also high in oil content. They typically contain 36% oil, which is roughly twice the level found in soybean, and the oil has a very low saturated fat content (˜4%). Pennycress represents a clear opportunity for sustainable optimization of agricultural systems. For example, in the US Midwest, ˜35M acres that remain idle could be planted with pennycress after a corn crop is harvested and before the next soybean crop is planted. Pennycress can serve as an important winter cover crop working within the no/low-till corn and soybean rotation to guard against soil erosion and improve overall field soil nitrogen and pest management.
Pennycress has an oil content that makes it highly desirable as a biofuel, and potentially as a food oil. Once the oil is obtained from pennycress, either from mechanical expeller pressing or hexane extraction, the resulting meal has a high protein level with a favorable amino acid profile that could provide nutritional benefits to animals. However, studies of pennycress processing have consistently demonstrated that the meal produced has a high level of non-digestible fiber, and as a result, not enough metabolizable energy to be competitive with high-value products like soybean and canola meals as an animal feed.